1. Field of the Invention
The present invention relates to a refrigerator, and more particularly, to a refrigerator having an ice bank capable of precisely transmitting a rotational force occurring from a driving motor in forward and backward directions to a rotation shaft of the ice bank.
2. Description of the Background Art
A refrigerator serves to store food items in a fresh state. The refrigerator may include an ice maker to make ice pieces, and an ice bank to receive therein ice pieces made by the ice maker.
Recently, a refrigerator having the ice maker and the ice bank is being widely used due to increased demands therefor.
Configurations and operations of the ice maker and the ice bank will be explained in brief.
Once ice pieces made by the ice maker drop into the ice bank, the ice pieces may be transferred, by a transfer unit, to an outlet of a case of the ice bank. Then, the ice pieces are transferred to a user through the outlet.
The transfer unit includes a fixed blade, and a rotatable blade crossing the fixed blade. The rotatable blade may be connected to a motor by a rotation shaft, thereby being rotated as the motor is driven.
The rotation shaft to which the rotatable blade is coupled to a joint rotatably disposed in the ice bank case. Accordingly, as a driving shaft of the motor is connected to the joint, the rotation shaft can rotate by a driving force of the motor.
However, the conventional ice bank has the following problems in a coupled state between the rotation shaft and the joint to each other.
More concretely, a screw thread is formed at the end of the rotation shaft having the rotatable blade coupled thereto, and the rotation shaft is made to penetrate the joint. Then, additional nuts are coupled to the screw thread disposed at the end of the rotation shaft, thereby coupling the rotation shaft and the joint to each other.
Here, when the motor is made to rotate in a reverse direction, the coupled state between the rotation shaft and the joint may be released. In order to solve the problem, the additional nuts are replaced by nuts having screw threads, or a bonding process is additionally performed. This may degrade the reliability of a coupled state between the rotation shaft and the joint, and cause the rotation shaft not to rotate in forward and backward directions.